The present invention relates generally to intelligent network systems for providing communications services, and specifically, to a novel service control system for providing real-time event processing services at each of a plurality of services nodes distributed throughout an intelligent network.
A network service is a function performed by a communications network, such as data or telephony, and its associated resources in response to an interaction with one or more subscribers. For example, a telephony network resident service, such as call forwarding or voice mail access, can be invoked by a subscriber by dialing a special sequence of digits. Other network services may be directed at assisting a network owner with security, validation, and authentication. Adding or modifying a service requires changes to be made in the communications network.
Most conventional telecommunication networks are composed of interconnected switches and communication services. These switches are controlled by integrated or imbedded processors operated by proprietary software or firmware designed by the switch manufacturer. Typically, the switch manufacturer""s software or firmware must support all functional aspects of service processing, call processing, facility processing and network management. This means that when a network owner wishes to implement a new service or modify an existing service, the software of every switch in the network must be revised by the various switch manufacturers.
The fact that the network contains different switch models from different manufacturers requires careful development, testing and deployment of the new software. The time required to develop, test and deploy the new software is lengthened because the code size at each switch grows larger and more complex with each now revision. Thus, this process can take several years. In addition, this increased complexity further burdens the switch processors, increases the chances for switch malfunction, and may require the modification or replacement of the switch.
Moreover, the fact that multiple network owners depend upon a common set of switch manufacturers results in two undesirable situations that limit competition. First, a manufacturers"" software release may attempt to incorporate changes requested by several network owners, thus preventing the network owners from truly differentiating their services from the services provided by their competition. This also forces some network owners to wait until the manufacturer incorporates requests from other network owners into the new release. Second, a switch software release incorporating a function as requested by one network owner to implement a new service can unintentionally become accessible to other network owners.
These problems have become intolerable as the demand for new network services has increased exponentially over the last five to ten years due to increased subscriber mobility, increased variety and bandwidth of traffic, dissolution of traditional numbering plans, more sophisticated services and increased competition. Thus, it is widely recognized that new network architectures need to incorporate a more flexible way of creating, deploying and executing service logic. In order to fully appreciate the novel architecture of the present invention hereinafter described, the following description of the relevant prior art is provided with reference to FIG. 1.
Referring to FIG. 1, a logical representation of various switching architectures, including the present invention, is shown. A monolithic switch, which is denoted generally as 20, contains service processing functions 22, call processing functions 24, facility processing functions 26 and a switch fabric 28. All of these functions 22, 24, 26 and 28 are hard-coded, intermixed and undifferentiated, as symbolized by the group 30. Moreover, functions 22, 24, 26 and 28 are designed by the switch manufacturer and operate on proprietary platforms that vary from manufacturer to manufacturer. As a result, these functions 22, 24, 26 and 28 cannot be modified without the aid of the manufacturer, which slows down service development and implementation, and increases the cost of bringing a new service to market. The development of new and innovative services, call processing, data processing, signal processing and network operations are, therefore, constrained by the manufacturer""s control over their proprietary switch hardware and software, and the inherent difficulty of establishing and implementing industry standards.
The service processing functions 22 are encoded within the monolithic switch 20 and only allow local control of this process based on local data contents and the number dialed. This local information is interpreted by a hard-coded process engine that carries out the encoded service function. The call processing functions 24 are hard-coded and provide call origination and call termination functions. This process actually brings up and takes down individual connections to complete a call. Likewise, the facility processing functions 26 are also hard-coded and provide all data processing relating to the physical resources involved in a call. The switch fabric 28 represents the hardware component of the switch and the computer to run the monolithic software provided by the switch manufacturer, such as Northern Telecom, Inc. The switch fabric 28 provides the physical facilities necessary to establish a connection and may include, but is not limited to, bearer devices (Tl""s and DSO""s), switching matrix devices (network planes and their processors), link layer signal processors (SS7, MTP, ISDN, LAPD) and specialized circuits (conference ports, audio tone detectors).
In an attempt to address the previously described problems, the International Telecommunications Union and the European Telecommunication Standards Institute endorsed the ITU-T Intelligent Network Standard (xe2x80x9cINxe2x80x9d). Similarly, Bellcore endorsed the Advanced Intelligent Network Standard (xe2x80x9cAINxe2x80x9d). Although these two standards differ in presentation and evolutionary state, they have almost identical objectives and basic concepts. Accordingly, these standards are viewed as a single network architecture in which the service processing functions 22 are separated from the switch.
Using the IN and AIN architectures, a network owner could presumably roll out a new service by creating and deploying a new Service Logic Program (xe2x80x9cSLPxe2x80x9d), which is essentially a table of Service Independent Building Blocks (xe2x80x9cSIBBxe2x80x9d) to be invoked during a given type of call. According to this approach, a number of specific element types inter-operate in conjunction with a SLP to provide services to network subscribers. As a result, any new or potential services are limited by the existing SIBBS.
The In or AIN architecture, which is denoted generally as 40, logically separates the functions of the monolithic switch 20 into a Service Control Point (xe2x80x9cSCPxe2x80x9d) 42, and a Service Switching Point (xe2x80x9cSSPxe2x80x9d) and Switching System 44. The SCP 42 contains the service processing functions 22, whereas the SSP and Switching System 44 contain the call processing functions 24, facility processing functions 26 and the switch fabric 28. In this case, the call processing functions 24, facility processing functions 26 and the switch fabric 28 are hard-coded, intermixed and undifferentiated, as symbolized by the group 46.
The Service Switching Point (xe2x80x9cSSPxe2x80x9d) is a functional module that resides at a switch in order to recognize when a subscriber""s signaling requires more than simple routing based solely upon the number dialed. The SSP suspends further handling of the call while it initiates a query for correct handling of the call to the remote SCP 42, which essentially acts as a database server for a number of switches. This division of processing results in the offloading of the infrequent, yet time consuming task of handling special service calls, from the switch. Furthermore, this moderate centralization draws a balance between having one readily modifiable, heavy burdened repository serving the whole network versus deploying a complete copy of the repository at every switch.
Referring now to FIG. 2, a diagram of a telecommunications system employing an IN or AIN architecture is shown and is denoted generally as 50. Various customer systems, such as an ISDN terminal 52, a first telephone 54, and a second telephone 56 are connected to the SSP and Switching System 44. The ISDN terminal 52 is connected to the SSP and Switching System 44 by signaling line 60 and transport line 62. The first telephone 54 is connected to the SSP and Switching System 44 by transport line 64. The second telephone 56 is connected to a remote switching system 66 by transport line 68 and the remote switching system 66 is connected to the SSP and Switching System 44 by transport line 70.
As previously described in reference to FIG. 1, the SSP 70 is a functional module that resides at a switch in order to recognize when a subscriber""s signaling requires more than simple routing based upon the number dialed. The SSP 70 suspends further handling of the call while it initiates a query for correct handling of the call. This query is sent in the form of SS7 messaging to a remote SCP 42. The Service Control Point 42 is so named because changing the database content at this location can alter the network function as it appears to subscribers connected through the many subtending switches. The query is sent through signaling line 72 to the Signal Transfer Point (xe2x80x9cSTPxe2x80x9d) 74, which is simply a router for SS7 messaging among these elements, and then through signaling line 76 to the SCP 42.
The Integrated Service Management System (xe2x80x9cISMSxe2x80x9d), 78 is envisioned as a management tool to deploy or alter services or to manage per-subscriber access to services. The ISMS 78 operates mainly by altering the operating logic and data stored within the SSP 70 and SCP 42. The ISMS 78 has various user interfaces 80 and 82. This ISMS 78 is connected to the SCP 42 by operations line 84, the SSP and Switching System 44 by operations line 86, and the Intelligent Peripheral (xe2x80x9cIPxe2x80x9d) 88 by operations line 90. The Intelligent Peripheral 88 is a device used to add functions to the network that are not available on the switches, such as a voice response or speech recognition system. The IP 88 is connected to the SSP and Switching System 44 by signaling line 92 and transport line 94.
Now referring to FIG. 2, the processing of a call in accordance with the prior art will be described. The call is initiated when the customer picks up the receiver and begins dialing. The SSP 70 at the company switch monitors the dialing and recognizes the trigger sequence. The SSP 70 suspends further handling of the call until service logic can be consulted. The SSP 70 then composes a standard SS7 message and sends it through STP(s) 74 to the SCP 42. The SCP 42 receives and decodes the message and invokes the SLP. The SLI interprets the SCP, which may call for actuating other functions such as database lookup for number translation. The SCP 42 returns an SS7 message to the SSP and Switching System 44 regarding the handling of the call or otherwise dispatches messages to the network elements to carry out the correct service. At the conclusion of the call, an SS7 message is sent among the switches to tear down the call and call detail records are created by each switch involved in the call. The call detail records are collected, correlated, and resolved offline for each call to derive billing for toll calls thus, completing call processing.
The IN and AIN architectures attempt to predefine a standard set of functions to support all foreseeable services. These standard functions are all hard-coded into various state machines in the switch. Unfortunately, any new functions, which are likely to arise in conjunction with new technologies or unforeseen service needs, cannot be implemented without an extensive overhaul and testing of the network software across many vendor platforms. Furthermore, if a new function requires changes to standardized call models, protocols, or interfaces, the implementation of the service utilizing that function may be delayed until the changes are ratified by an industry standards group. But even as draft standards have attempted to broaden the set of IN and AIN supported functions, equipment suppliers have refused to endorse these draft standards due to the staggering increase in code complexity. A detailed flow chart describing the process for generic service creation according to the prior art may be found in above-mentioned, commonly-owned, co-pending U.S. patent application Ser. No. 09/128,937 filed Aug. 5, 1998 entitled xe2x80x9cIntelligent Call Platform for an Intelligent Network Distributed Architecturexe2x80x9d, the contents and disclosure of which is incorporated by reference as if fully set forth herein.
In further view of FIG. 2, other limitations of the IN and AIN architecture arise from having the call processing and facility processing functions, namely, the SSP 70, operating within the switch. As a result, these functions must be provided by each switch manufacturer using their proprietary software. Network owners are, therefore, still heavily dependent upon manufacturer software releases to support new functions. To further complicate the matter, the network owner cannot test SSP 70 modules in conjunction with other modules in a unified development and test environment. Moreover, there is no assurance that an SSP 70 intended for a switch manufacturer""s processing environment will be compatible with the network owner""s service creation environment.
This dependency of multiple network owners upon a common set of switch manufacturers results in two undesirable situations that limit competition. First, a manufacturer""s software release may attempt to incorporate changes requested by several network owners, thus preventing the network owners from truly differentiating their services from the services provided by their competition. This also forces some network owners to wait until he manufacturer incorporates requests from other network owners into the new release. Second, a switch software release incorporating a function as requested by one network owner to implement a new service can unintentionally become accessible to other network owners. Therefore, despite the intentions of the IN and AIN architects, the network owner""s creation, testing and deployment of new services is still impeded because the network owner does not have complete control of, or access to, the functional elements that shape network service behavior.
In another attempt to solve these problems, as disclosed in pending U.S. patent application Ser. No. 08/580,712, a Separate Switch Intelligence and Switch Fabric (xe2x80x9cSSI/SFxe2x80x9d) architecture, which is referred to generally as 150 (FIG. 1), logically separates the SSP 70 from the Switching System 44. Now referring back to FIG. 1, the switch intelligence 152 contains the call processing functions 24 and facility processing functions 26 that are encoded in discrete state tables with corresponding hard-coded state machine engines, which is symbolized by circles 154 and 156. The interface between the switch fabric functions 158 and switch intelligence functions 152 may be extended through a communications network such that the switch fabric 158 and switch intelligence 152 may not necessarily be physically located together, by executed within the same processor or even have a one-to-one correspondence. In turn, the switch intelligence 152 provides a consistent interface of simple non-service-specific, non-manufacturer-specific functions common to all switches.
An Intelligent Computing Complex (xe2x80x9cICCxe2x80x9d) 160, contains the service processing functions 22 and communicates with multiple switch intelligence elements 152. This approach offers the network owner advantages in flexible service implementation because all but the most elementary functions are moved outside the realm of the manufacturer-specific code. Further improvements may be realized by providing a more unified environment for the creation, development, test and execution of service logic.
As previously discussed, current network switches are based upon monolithic proprietary hardware and software. Although network switches can cost millions of dollars, such equipment is relatively slow in terms of processing speed when viewed in light of currently available computing technology. For example, these switches are based on Reduced-Instruction Set Computing (xe2x80x9cRISCxe2x80x9d) processors running in the range of 60 MHz and communicate with each other using a data communications protocol, such as X.25, that typically supports a transmission rate of 9.6 Kb/s between various platforms in a switching network. This is extremely slow when compared to personal computers that contain processors running at 200 MHz or above and high end computer workstations that offer 150 Mb/s FDDI and ATM interfaces. Accordingly, network owners need to be able to use high-end workstations instead of proprietary hardware.
The present invention is directed to a service control system for providing real-time service processing all of the events and service requests received at a resource complex, e.g., switch or router, physically associated with each of a plurality of distributed service nodes of an intelligent communications network.
Generally, the service control component of the invention is capable of instructing the intelligent network resource complex, e.g., ATM switch, Internet gateway, Intelligent Peripheral, or other switch or router resource, in the processing of service requests, and further encompasses the intelligence required to process the service requests. Particularly, the intelligence built in enables Service Control components to interact with other intelligent network components to access additional logic or to obtain information (service or user data) required to process a service logic instance. Service Control interfaces and interacts with the resource complex and a local data management system during real time service processing and, possesses the logic and processing capability required to handle intelligent network provided service attempts. Service Control is managed, updated and administered by a service administrator and data management components of the intelligent network. The intelligent network provides intelligent call processing services independent of and transparent to the call switching platform or resource complex in which a call is received, and is readily adapted to handle call events. Thus, the dependency for expensive, vendor-specific hardware, operating systems and switching platforms, is eliminated. The distributed intelligent network additionally supports location-independent event processing service execution, enabling the modular software logic programs to be run virtually anywhere in the architecture, and provides location-independent communications among these distributed processes, thus further eliminating the need for specialized service nodes.
More particularly, the invention controls one or more processes which are started when a service request is sent into Service Control component by the resource complex. Service Control interacts with other components to access the required data necessary to provide the requested service. When the requested service behavior sequence is complete or when the service user(s) withdraw from using the service, the process is complete. All the resources involved in serving the service requester on behalf of the request are released at the end of the processing. Each service request initiates one instance (thread) of service processing, thus providing heavy parallel processing with less contingency or bottlenecks.
Preferably, each service thread instance maintains its own event queue with service control providing for the asynchronous channeling events received for a particular call instance onto the appropriate service thread queue for storage and execution thereof according to a pre-determined priority associated with the event. Service control additionally provides for the asynchronous channeling of events to the switch/resource complex, or other executing service logic programs therewith, with the thread instance blocking as it waits for a response.
According to the invention, the major responsibilities of the Service Control component include: accepting and processing events or requests from a switching platform or other external resources; identifying and invoking service logic programs to process the incoming request; requesting service or subscriber related data from a data management storage device through a network operating system (NOS) or directly via a database application programming interface (API); updating service or subscriber related data to a Data Management component through NOS; providing capability to send prioritized events and messages to the resource complex and other service logic programs to control user interaction; receiving message sets from the resource complexxe2x80x94including user input, e.g., PIN, (dual tone multi-frequency) DTMF digits corresponding to a selected menu item, etc.; maintaining states and data of all the participants involved in the same instance of service processing; and, generating billing records and transmitting them to billing record generation function of the Data Management component.
The various features of novelty which characterize the invention are pointed out with particularity in the claims annexed to and forming a part of the disclosure. For a better understanding of the invention, its operating advantages, and specific objects attained by its use, reference should be had to the drawings and descriptive matter in which there are illustrated and described preferred embodiments of the invention.